Ingredient Information

Function

Ferrous gluconate or iron (II) gluconate is an iron compound. It is added to foods to fortify them with iron and is used for better absorption into the blood. Ferrous gluconate is also used to impart a pure black color to olives that have been picked when green and artificially “ripened.“ The iron reacts with tannins in the olive’s skin to turn it black. Moreover, ferrous gluconate is sold as a dietary supplement.

Other Use and Industries

Ferrous gluconate is used as a supplement in iron pills and multivitamins. It is taken to increase blood iron levels in people with deficiencies, such as when women are pregnant or in cases of anemia.

Health Effects

Ferrous gluconate is effective in treating or preventing anemia, but consuming too much can be toxic. For this reason, women who are pregnant should not take ferrous gluconate unless advised to by a doctor. It has been shown that those women who were not anemic and took ferrous gluconate had more incidences of high blood pressure and delivered smaller babies.

Furthermore, ferrous gluconate tablets taken in prescribed quantities may cause constipation and nausea. And in liquid supplement form, it can stain teeth black. Meanwhile, ferrous gluconate should not be used in foods that contain potassium sorbate as well as ascorbic acid together. This is because ferrous gluconate and ascorbic acid can react with potassium sorbate to produce potentially cancer-causing substances. Overall, consumption of ferrous gluconate pills in high doses is dangerous and may be fatal.

Origins

Ferrous gluconate is the iron salt of gluconic acid. Gluconic acid is a naturally occuring organic acid present in honey, wine, and fruits. Ferrous gluconate is produced by combining a water-soluble iron salt with gluconic acid, and the gluconic acid is obtained through the microbial fermentation of sugar by Aspergillus niger. Ferrous gluconate is available as an iron supplement in capsule, powder, and liquid form.